1. Technical Field
The present invention relates to separators, separator cartridges, and separator systems.
2. Related Art
Methods of chemical analysis, chemical synthesis, and other procedures including various analyses in bio-related fields using a microfluidic chip that includes microchannels in a glass substrate or the like have gained attention. The microfluidic chip, also known as a micro total analytical system (micro TAS) or a lab-on-a-chip, has advantages such as smaller amounts of samples and reagents, shorter reaction time, and less waste over common devices. Because of these advantages, the microfluidic chip is expected to have a wide range of applications, including medical diagnoses, on-site analyses of environment and food, and production of drugs and chemicals. Because the microfluidic chip requires only small amounts of reagent, the cost of tests can be reduced. Requiring small amounts of samples and reagents means a greatly shorter reaction time and improved test efficiency. Because specimens such as a sample blood are used in small amounts, the use of the microfluidic chip for medical diagnoses is particularly advantageous in terms of reducing the burden on patients.
Sunitha Nagrath et al., Isolation of rare circulating tumour cells in cancer patients by microchip technology, vol. 450|20/27, December 2007| doi:10.1038/nature06385 LETTERS describes a microchannel device that includes a plurality of cylindrical microposts disposed at regular intervals. In the microchannel device, an adherent factor is immobilized on the side surfaces of the cylindrical microposts, and the cancer cells in the blood flown in the microchannel device are removed by the adhesion of the adherent factor immobilized on the side surfaces of the cylindrical microposts. However, in the microchannel device, the ability of the adherent factor to adhere to the cancer cells is highly dependent on the flow rate of the blood, and the size and intervals of the cylindrical microposts. For example, when the blood flow rate is low, the cancer cells have less opportunity to contact the adherent factor, and only small numbers of cancer cells may be allowed to adhere to the cylindrical microposts. When the blood flow rate is high, there are cases where the cancer cells adhered to the cylindrical microposts are washed away. The cancer cells have only small opportunity to contact the adherent factor when the intervals between the cylindrical microposts are too large, and only small numbers of cancer cells may be allowed to adhere to the cylindrical microposts. Excessively small intervals between the cylindrical microposts increase the resistance against the blood flow, and the channels may be clogged by the adhered cancer cells.